Apple Computer's latest Mac OS X security update misses several dangerous vulnerabilities and is causing system hangs and boot-up problems for some users, according to information reaching eWEEK.

Less than a week after Apple shipped a mega-update with fixes for a whopping 43 Mac OS X and QuickTime vulnerabilities, independent researcher Tom Ferris said that multiple Safari browser flaws remain unpatched.

Ferris, who has become a bit of a gadfly for Apple, reported the Safari vulnerabilities to Apple on April 19, but after testing the Security Update 2006-003, he told eWEEK the issues have not yet been addressed.

Ferris, who goes by the online moniker of "badpack3t," said the Safari bugs causes the application to crash and may allow a malicious attacker to execute arbitrary code.

On his Security-Protocols.com Web site, Ferris has released technical information on the flaws alongside proof-of-concept code to reproduce the browser crashes.

Back in April, Ferris also flagged a heap overflow vulnerability when specially crafted ".bmp" are processed and decompressed.

Although the Mac OS X update promised a fix for that bug, Ferris insists the underlying issue has not been addressed.

"[The update] does prevent the crash when opening [my] original proof-of-concept file. But after slightly modifying that file, I was able to trigger the same issue with the latest security update installed," Ferris said.